Tow chain

Abstract

A tow chain consisting of a series of links which are joined together in a hingeable manner by means of vertical shafts. These links have such a towing pattern that the total sum of horizontal widths of the contact surfaces of two successive links of the tow chain are equal to or slightly smaller than the maximum horizontal width of the tow chain.

I claim: 
     
       1. A tow chain comprising: a series of successive links, each link having at least one bottom contact surface which is supported on a support surface;   vertical shafts for interconnecting said successive links in a hingeable manner; and   wherein each of the bottom contact surfaces has a horizontal width, and the total sum of the horizontal widths of the bottom contact surfaces of two successive links of said chain are equal to or slightly smaller than a maximum horizontal width of said tow chain.   
     
     
       2. The tow chain of claim 1, wherein one of two successive links of said tow chain has a single contact surface, and the other of said two successive links has two bottom contact surfaces. 
     
     
       3. The tow chain of claim 1, wherein said successive links each comprise at least one downwardly directed protrusion with a bottom surface, and said contact surfaces of said successive links are formed by said bottom surfaces of said protrusions. 
     
     
       4. The tow chain of claim 2, wherein said successive links are alternately structured such that a first successive link comprises a single downwardly directed protrusion with a bottom surface forming a first contact surface, and a second successive link comprises two downwardly directed protrusions each having a bottom surface thereby forming second and third contact surfaces, wherein a horizontal width of the first contact surface is equal to or slightly smaller than a distance between the second and third contact surfaces of the second link. 
     
     
       5. The tow chain of claim 4, wherein said single protrusion of said first successive link is situated centrally in the longitudinal direction of the tow chain. 
     
     
       6. The tow chain of claim 4, wherein said second successive link has a reverse U-shaped profile with two alternate flanges, said alternate flanges forming said two downwardly directed protrusions. 
     
     
       7. The tow chain of claim 1, wherein said vertical shafts have top and bottom ends, said bottom end being situated at a higher level than the contact surfaces of corresponding successive links. 
     
     
       8. The tow chain of claim 1, wherein each of said successive links further comprise side edges which are inwardly bent.